The overall goal of this project is to use radiation hybrid mapping to establish a contiguous physical map of the human genome with an average resolution of 100 kb between adjacent markers. Our aim is to determine the order of 30,000 unique DNA landmarks with respect to one another and to obtain an estimate of the physical distance between adjacent markers. Two different sets of radiation hybrid cell lines consisting of approximately 85 independent cell lines per set will be used to construct the map. Set 1 hybrids, which presently exist, will be scored with 6000 selected markers over the first 12 to 18 months of the grant to generate a contiguous physical map of the human genome with an average resolution of 500 kb. Since the Set 1 hybrids do not contain a sufficient number of X-ray breaks to generate a 100 kb average resolution map of the genome, we will generate a second set of radiation hybrids (Set 2) in the first year of the grant. Set 2 hybrids will be scored with 30,000 markers over the remaining four years to generate a contiguous map of the genome with an average resolution of 100 kb. 3000 of the markers on our maps will consist of polymorphic loci and/or genes previously laced on meiotic and/or physical maps by other scientists. These 3000 markers will provide the basis for integration of our maps with preexisting maps. In addition, DNA from Set 1 cell lines, as well as the cell liens themselves, will be made available to other genome mappers, providing a basis for integration of our maps with other maps presently under construction. Since the 30,000 markers scored on Set 2 hybrids will be designed to span the majority of the estimated 20,000 Sfi 1 restriction map of the human genome (Project 3). Such integration will allow for a comparison of order and distance information generated from radiation hybrids with that obtained from uncloned genomic DNA.